December 11, 2002 Feature
Story
High
Tide for the Colorado River
Utah
State Scientist Helps Restore Ecosystem
 The
first flood was a practice run, as it turned out.
Gates holding back the collected waters of the Colorado River
were opened in 1996, and the river, trapped behind the Glen
Canyon Dam since 1963, surged free.
The goal was to rebuild sandbars and beaches worn away by the
dam’s regulated flow and restore wildlife and fish habitat
to a more natural state — in short, to bring a little
wildness back to the thoroughly tamed Colorado River ecosystem.
But the roiling, mud-brown floodwaters soon ran crystal clear.
The Nov. 29 issue of the science journal "Nature"
highlighted studies conducted by Utah State University geomorphologist
Jack Schmidt. His studies determined that there was not enough
sediment in the floodwaters to restore beaches and riverbanks.
Instead, Schmidt said, the scouring effects of the deluge added
to erosion problems. The flood initially built up riverbanks,
but the net effect, after the floodwaters had boiled through
the channel, was destructive. Some sandbars were partially swept
downstream.
 The
attempt was also a lose-lose situation for hydroelectric companies,
who picked up the $2.5 million tab in lost electricity generation.
The project failed.
But not completely, according to "Nature."
"It was a tremendous success as an experiment," Schmidt
said. "We learned important things we could not have known
had the experiment not been run."
Schmidt and his colleagues carefully gleaned information from
the trial run and believe they now have the knowledge to ensure
that a second flood will be successful.
Timing, Schmidt discovered, is everything. For hundreds of thousands
of years before Glen Canyon Dam was constructed, the river rose
and fell in rhythm with the seasons. Its muddy, brown waters
were replenished each spring by an icy-clear, ferocious runoff.
The scouring torrent swept debris downstream, depositing sediment
on sandbars and beaches, creating riverbanks and habitat.
The next flood attempt, Schmidt said, will be timed to coincide
with an infusion of fresh sediment from the Colorado’s
upstream tributaries, brought by end of summer rains.
Many stakeholders — state governments, Native American
tribes, hydroelectric power companies, National Park rangers,
conservationists, recreationists, tour guides and archeologists
— will be watching the second flood anxiously.
The cold-running river has generated a lot of heat. Power companies
and environmental groups have clashing interests, and river
restoration efforts may interrupt the smooth flow of hydroelectric
power to 15 states.
But according to "Nature," stakeholders all agree
the river is in trouble. The historic river has been washed
downstream, its beaches in a state of deterioration. The Colorado
is now managed to achieve a steady, regulated flow. The unnaturally
cold, clear water has given rise to non-native predatory fish
populations, while native fish populations have plummeted. Ninety
percent of the sediment load settles on the bottom of Lake Powell.
Scientists and planners agree that a second flood is risky because
of the long-lasting regional drought, which has lowered the
flow and reduced sediment load. But planners are moving forward
— cautiously. The carefully negotiated flood plan is part
of a compromise agreement. Interested parties would rather thrash
out their differences over a negotiating table than in court,
and they agree that restoration is long overdue.
Now all parties are waiting for the green light, which is expected
to be issued by Secretary of the Interior Gale Norton in the
near future.
"We have river guides, power customers and environmentalists
looking over our shoulders," said Schmidt. "It’s
a pain in the neck and time-consuming. Collecting data is difficult
and expensive.
"But it’s one of the most beautiful places on Earth.
I would hope people would care about it."
Writer: Nadene Steinhoff, 435-797-1429, nadene.Steinhoff@usu.edu
Contact: Jack Schmidt, 435-1791, jackschmidt@cnr.usu.edu
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